Technical Field
The described embodiments generally relate to methods of modeling and building models of oil and gas deposits. In particular, the described embodiments relate to a computer-implemented method, computerized system, and a computer readable medium designed for automated identification of surfaces for building a geologic-hydrodynamic model of an oil and gas deposit based on seismic data.
Description of the Related Art
A method for building 3D geological structures based on surface data is presented in G. Caumon et al., “Surface-Based 3D Modeling of Geological Structures”, 23 Sep. 2009, which describes a close integration of surface data in geological modeling. The aforesaid method identifies nodes on the surface of grid boundary, which intersect other surfaces. Limitations on the thickness and range are introduced during interpolation to build surfaces spaced a given distance apart. The distance is evaluated on a vector field.
A method of geophysical exploration for identifying oil-and-gas features is described in RU 2289829 C1, G01V 11/00, 20, Dec. 2006, which describes optimizing the location of deep wells at oil-and-gas features by a set of data of land seismics, as well as electrical, magnetic, and gravity exploration; electric, radioactive, acoustic, seismic, magnetic, and gravity logging; core analysis and well tests. Data of acoustic, seismic, electric, radioactive, magnetic, and gravity logging, as well as laboratory core studies are used to build stiffness, electric, magnetic, and gravimetric models of the target interval of geological section in wells, evaluate geophysical synthesized traces, which are used to carry out Spectral-time analysis of seismic records (SWAN) and to determine model SVO and their spectral-time attributes (STA). The spectral-time attributes (STA) are the ratios of the energy of high frequencies and long times to the energy of low frequencies and short times, as well as the products of specific spectral density multiplied by the weighted mean frequency and time or by maximal frequency and time of energy spectra of SVAN column along the axes of frequencies and times.
Various methods for building digital geological models of oil-and-gas deposits and designing their development with the use of digital geological models proposed by Geoneftegas Company are also known, see www.geoneftegaz.ru/models/mod.htm. The aforesaid company suggests solutions for implementing a digital geological model, built with the use of a technology allowing the reservoir properties and the oil-bearing capacity of carbonate and terrigenous beds to be studied in complicated media with tectonic and lithological screening, enabling the estimation of oil reserves by commercial categories. This solution is used to calculate geological-technological hydrodynamic models and to optimize development projects. The application of this technology for forecasting the reservoir properties and oil-bearing capacity makes it possible to build sound 3D geological models with minimal volume of deep drilling. Their involvement in the process of calculation and analysis of development process characteristics allows the formation of optimal process schemes and accelerates the commissioning of new facilities. The analysis of verifiability of reservoir parameter estimates, including effective thickness, porosity, and fluid type by data of newly drilled wells suggests good agreement between the results.
A method for the control of geometric and hydrodynamics parameters of reservoir hydraulic fracturing is described in RU 2390805 C1, G01V 5/12, 27, May 2012. In the aforesaid method, before reservoir fracturing, radon concentration were measured in pits 50 to 70 cm in depth in a grid with 50 m step within a 400 m×400 m square area centered in the well mouth. Data of surface surveys are used to draw lines of geodynamic zones, which can be related to newly formed fracture systems caused by hydraulic fracturing (because of high pressure). Radon indicator studies are carried out in the well before the hydraulic fracturing, and the engineering conditions of the well are determined: behind-casing fluid movement, if any, its direction, the percentage distribution of the pumped liquid between such flows, water injection profile based on data of measurements with three repetitions, and the permeability.
A drawback of the described conventional solutions is that they fail to ensure the building of a high-accuracy model of an oil-and-gas deposit based on seismic data alone. Therefore, new and improved techniques capable of generating of high-accuracy geological models based on seismic data are needed.